Lithium ion batteries currently constitute the leading technology within the field of rechargeable batteries, and they dominate the battery market for portable electronics. Applications for lithium ion batteries in electrical vehicles or in storage technologies for wind or solar energy, for example, nevertheless necessitate the development of rechargeable battery technologies and active materials having significantly higher specific energies and capacities than have hitherto been available commercially or at all. There is therefore need not only for an improvement of existing electrode materials, but also for development of new materials with suitability as the active material for lithium ion batteries.
New electrode materials follow in principle two different mechanisms of lithium acceptance, either the reversible formation of an alloy with lithium, as in the case of silicon, tin, antimony, aluminum, or zinc, or the so-called conversion reactions, such as for cobalt oxide, nickel oxide, iron oxide, or copper oxide, for example. Alloy-forming materials, however, suffer severe changes in volume as a result of lithium acceptance and release, thereby destroying the material and causing a loss of electronic contact between active material and current collector. Nevertheless, materials which form reversibly alloys with lithium are currently viewed as the more promising for short-term industrial applications. In 2005, for example, Sony announced the marketing of the Nexelion™ battery, which is based on an Sn—Co—C composite as anode material. Research is presently focused on silicon-based or tin-based electrode materials, whereas zinc, as a potential replacement for the graphite normally used commercially as anode material, is finding little attention, despite promising results achieved with ZnO—Fe2O3—, ZnO1-xSx—, and Al2O3-doped thin-film ZnO structures. However, the electrodes in question have been produced by means of complex methods such as magnetron sputtering, and only thin layers of the active material are characterized. These layers are poorly suited as active material for lithium ion cells with high energy density. Apart from the less-suitable methods of electrode production for industrial applications, furthermore, the materials exhibit an inadequate specific capacity. Moreover, the irreversible formation of Li2O in the first cycle leads to a loss of capacity.
Specification U.S. Pat. No. 3,330,697 further describes the so-called Pecchini process for producing perowskitic compounds. Disadvantages of this, however, include firstly the volume expansion that occurs and secondly the formation of nitrogen-containing gases in the course of this combustion-based synthesis process starting from metal nitrates.